Band III

Band III is the name of the range of radio frequencies within the very high frequency (VHF) part of the electromagnetic spectrum from 174 to 240 megahertz (MHz). It is primarily used for radio and television broadcasting. It is also called high-band VHF, in contrast to Bands I and II.

Broadcast Television

North America

The band is subdivided into seven channels for television broadcasting, each occupying 6 MHz.[1]

Channel Frequency Range
7174-180 MHz
8180-186 MHz
9186-192 MHz
10192-198 MHz
11198-204 MHz
12204-210 MHz
13210-216 MHz

Europe

European Band III allocations vary from country to country, with channel widths of 7 or 8 MHz.

The standard channel allocations for European countries that use System B with 7 MHz channel spacing are as follows:

Channel Frequency Range
E5174-181 MHz
E6181-188 MHz
E7188-195 MHz
E8195-202 MHz
E9202-209 MHz
E10209-216 MHz
E11216-223 MHz
E12223-230 MHz

The Irish (8 MHz) system is shown below.

Channel Frequency Range
D174-182 MHz
E182-190 MHz
F190-198 MHz
G198-206 MHz
H206-214 MHz
i214-222 MHz
J222-230 MHz

Oceania

Australia has allocated 8 channels in Band III for digital television, each with 7 MHz bandwidth.

Channel Frequency Range
6174-181 MHz
7181-188 MHz
8188-195 MHz
9195-202 MHz
9A202-209 MHz
10209-216 MHz
11216-223 MHz
12223-230 MHz

Russia and other former members of OIRT

Russian analog television is transmitted using System D with 8 MHz channel bandwidth.

Channel Frequency Range
6174-182 MHz
7182-190 MHz
8190-198 MHz
9198-206 MHz
10206-214 MHz
11214-222 MHz
12222-230 MHz

Radio

The band came into use for radio broadcasting at the turn of the 21st century and is used for Digital Audio Broadcasting.

It is subdivided into a number of frequency blocks:

Block Centre Frequency
5A174.928 MHz
5B176.640 MHz
5C178.352 MHz
5D180.064 MHz
6A181.936 MHz
6B183.648 MHz
6C185.360 MHz
6D187.072 MHz
7A188.928 MHz
7B190.640 MHz
7C192.352 MHz
7D194.064 MHz
8A195.936 MHz
8B197.648 MHz
8C199.360 MHz
8D201.072 MHz
9A202.928 MHz
9B204.640 MHz
9C206.352 MHz
9D208.064 MHz
10A209.936 MHz
10B211.648 MHz
10C213.360 MHz
10D215.072 MHz
10N210.096 MHz
11A216.928 MHz
11B218.640 MHz
11C220.352 MHz
11D222.064 MHz
11N217.088 MHz
12A223.936 MHz
12B225.648 MHz
12C227.360 MHz
12D229.072 MHz
12N224.096 MHz
13A230.784 MHz
13B232.496 MHz
13C234.208 MHz
13D235.776 MHz
13E237.488 MHz
13F239.200 MHz

Worldwide usage

Europe

In the UK and part of Ireland, Band III was originally used for monochrome 405-line television; however, this was discontinued by the mid-1980s. Other European countries (including Ireland) continued to use Band III for analogue 625-line colour television.

Digital television in the DVB-T standard can be used in conjunction with VHF Band III and is used as such in some places. The use of sub-band 2 and sub-band 3 band for Digital Audio Broadcasting is now being widely adopted. Sub-band 1 is used for MPT-1327 trunked PMR radio, remote wireless microphones and PMSE links.

North America

In North America, use of the band for television broadcasts is still widespread. Favorable propagation characteristics and reasonable power limits (up to 65 kW for full-power digital television, versus 20 kW or less on VHF Band I) has meant that many US broadcasters elected to move their full-power ATSC stations from UHF frequencies to Band III VHF when all full-power NTSC analog television services in the US shut down in 2009.[2]

References
  1. TV Frequency Table csgnetwork.com
  2. FCC TV Query: US DTV construction permit listings for VHF Band I (ch 2-6) and III (ch 7-13)
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